Tomato plant problems

[popeyespappy]

Did it start out as spots, is it mostly the lower leaves or the upper leaves.  How many leaves on any given cluster are affected?  Has it been really hot (and are you watering more to keep them from wilting)?  Is the soil damp or dry?

Today was the first time we noticed it. All the leaves on one branch were affected to some degree. With some more on another limb.

We've had very few days without rain lately so little watering required. The box drains very well, but the soil has been pretty wet.